不规则形状A301氨合成催化剂内扩散有效因子

对于不规则形状A301氨合成催化剂,测定了其形状系数和球化的当量直径及高压下本征动力学方程,用SPSR法测定了不规则催化剂颗粒的曲折因子,根据多组分单一反应等温球形A301氨合成催化剂内反应-扩散-维模型,用正交配置法结合解非线性方程组的Broyden拟牛顿法求解了模型,获得了催化剂粒内各组分的浓度分布和催化剂的内扩散有效因子.利用所测得的高压下A301催化剂的总体速率对模型进行了检验,模型计算值和实验值吻合,表明球化模型和所得当量直径、曲折因子等模型参数可用于描述A30l催化剂内的反应-扩散过程及工程设计计算.

INTRAPARTICLE DIFFUSION EFFICIENCY FACTOR OF IRREGULAR A301 AMMONIA SYNTHESIS CATALYST

The irregular A301 ammonia synthesis catalyst is spheroidized by means of shape factor and equivalent diameter. The tortuosity factor of irregular A301 catalyst is determined by single pellet string reactor method (SPSRM). So a one - dimensional isothermal multi- component diffusion ?reaction model is established in the irregular A301 ammonia synthesis catalyst based on the intrinsic kinetics under high pressure. The orthogonal collocation method as well as Broyden method was used to solve the model equations. The intraparticle diffusion efficiency factor and the concentration distributions of individual components in the catalyst are obtained. The model is verified by the global kinetics data under high pressure obtained in a gradientless reactor. The calculation data agree well with experimental data, so the spheroidized model can be used to describe the diffusion- reaction process in the irregular catalyst and to calculate the intraparticle diffusion efficiency for engineering design.